The European Union has suffered several problems in recent years, which triggers a proactive action by its institutions to generate a united citizenry and awareness of the importance of the EU. In the field of higher education, the European Strategy for Universities born in 2019 aims to strengthen and developed a common university system. The Erasmus program has traditionally been identified as the main driver of integration, but the emergence of European universities may mark a new phase in the shaping of the European Public Sphere (EPS). In this sense, social media are the key communication tool for higher education centers. The objective of this work is to examine the activity on social media of the 40 consortia of European Universities belonging to the first and second calls. First, the presence on the different social networks of these entities is analyzed to establish a map of the alliances, based on the number of social networks used, the volume of followers, the coordinating university and the year of the call. After identifying Twitter as the most used network, a content analysis is carried out on 12 variables of all the messages published by these consortia since their creation, with the aim of determining whether the content published on their Twitter accounts is professional in tone. The results reveal scant interactivity that does not take advantage of the potential of social networks. However, there is a certain influence of the national cultures in terms of use of digital platforms in the different countries that head each consortium, with Spain and France being rather remarkable in this aspect. Likewise, the advantage acquired by first-generation consortia boosts their greater impact. This leads to a reflection upon the true transnational dimension of the communication implemented by these universities.